Calculus 3 Lecture 13.2: Limits and Continuity of Multivariable Functions (with Squeeze Th.)

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  • Опубліковано 19 вер 2024
  • Calculus 3 Lecture 13.2: Limits and Continuity of Multivariable Functions: How to show a limit exits or Does Not Exist for Multivariable Functions (including Squeeze Theorem). Also, how to determine regions of continuity.

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    @lolipopscandy62 8 років тому +992

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      @JawadAli-tj3ec 7 років тому +2

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  • @learningleopard996
    @learningleopard996 3 роки тому +286

    Intro to multivariable limits: 0:00
    Showing a limit (with two variables) does not exist: 26:54
    Showing a limit (with three variables) does not exist: 1:12:19
    Showing a limit does exist: 1:32:07
    changing to polar coordinates: 1:32:28
    Continuity (domain and compositions): 1:41:47
    Summary of computing limits: 2:06:56 - 2:07:24
    Squeeze theorem (converting to inequalities): 2:07:26

  • @grantedwards8546
    @grantedwards8546 8 років тому +292

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    @hugojulia7145 4 роки тому +121

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  • @sujitsuram5075
    @sujitsuram5075 4 роки тому +132

    conceptual talk until 00:00
    Examples of 2 dependent variables: 24:00
    Examples of 3 dependent variables: 1:12:15
    Squeeze theorem : 2:07:25

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      @ProfessorLeonard  5 років тому

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    @ishitapandey6349 4 роки тому +5

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  • @xbriitbx
    @xbriitbx 6 років тому +1

    Thank you for showing how to apply Squeeze Theorem to these problems!!! My teacher tried to explain it to us in half of a lecture and you did it under 10 minutes in a way that I can understand!

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    @ninjamonk37 8 років тому +7

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    • @ProfessorLeonard
      @ProfessorLeonard  8 років тому +41

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      @presidentevil9951 7 років тому

      Could you also give more examples of proving the limit DOES exist in different ways and what methods to use when?

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    @georgesadler7830 2 роки тому

    Professor Leonard, thank you for another well organized video/lecture on Limits and Continuity on Multivariable Functions with the classic Squeeze Theorem in Calculus Three. These concepts are introduced in Calculus One, which improve my understanding of the subject in Multivariable Calculus.

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    @aaronguerrero592 11 місяців тому

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    @roadtoad3484 4 роки тому

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  • @tomasvenegas9600
    @tomasvenegas9600 Рік тому +1

    i think you might be wrong here. When you use for example polar coordinates and you get a number it's not strong enough to prove that the limit exists, you'd have to use that number as a candidate of a posible value of the limit and then plug it the squeeze theorem or the epsilon-delta definition.
    Then just then you can prove the limit exists.

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    @kezianathaniel2901 5 років тому +1

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  • @gmcenroe
    @gmcenroe Рік тому

    In this first and second example if you do a 3D plot (Used Mathematica in my case) you can see that these functions are not continuous at (0,0) but has a cusp along one axis at the point (0,0) in example 1 and a cusp along the -x,y and x.y diagonals in example 2 therefore the limit is undefined. In the example lim as (x,y)->(1,0) of (2xy-2y)/(x^2 +y^2 -2x +1)Professor Leonard found that the lim as y->0 of 2y^2/2y^2 =0 presumably because this reduced to the lim y->0 of 2y^2/2y^2 is 0/0 =1 and concluded that the limit was undefined. However Mathematica finds this limit of the base limite to be 0, so the original problem has a limit of 0 also which is also what Mathematica found. This is in agreement with the plot of the surface and examining the point (x,y) = (1,0) Mathematica's determination of the original limit to be 0, so I believe his answer is differant. I guess this depends on your definition of 0/0 or it could be a bug in Mathematica. Please comment Professor Leonard and others if you can. Time point 1:11:48.

  • @SweRaider1993
    @SweRaider1993 8 років тому +1

    Thank you so much! I'm surprised my book never mentions the squeeze theorem and instead goes through a bunch of other non-sensical stuff... You made it all perfectly clear, and the theorem kind of makes sense intuitively as well.

  • @waltercarrillo6065
    @waltercarrillo6065 5 років тому

    Great professor, those students must be proud of him. D for done.

  • @Bodinie
    @Bodinie 7 років тому +3

    Professor Leonard, Thank you for your videos they have been a big help to supplement my course work. Does your class deal with epsilon-delta definition to prove limits of multi-variable functions?

  • @susanlove9620
    @susanlove9620 2 роки тому

    reviewing again, cuz i want it to be like...hate adding... like geometry when i was young. honestly, this is where it gets exciting. also, each time i study a lesson, as i understand it even more clearly, i realize even more what a good teacher you are.

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    @mohammedeldakak4592 5 років тому +1

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    @revivemuzunzandare479 6 років тому +1

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    @austinpolk7213 2 роки тому

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    @davekaushik4863 2 роки тому

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  • @shubhamjain31
    @shubhamjain31 7 років тому +11

    hello sir..
    I wanted to know what if the question asks to prove that limit exists...

    • @abdullahmansoor5444
      @abdullahmansoor5444 4 роки тому +1

      Hey bud, We can always use the squeeze theorem to prove that a limit exists. Refer to 2:07:00 in the video

  • @andream8671
    @andream8671 4 роки тому +1

    My professor didn’t e explain anything, sadly. I have an exam tonight due at 12am, and I’m here trying to understand. Now I’m stuck trying to understand everything. Thank you for helping and existing though.

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    @Ali-qc3ym 6 років тому +1

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    @maths4noobs 2 роки тому

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